This invention relates to systems and methods for producing self-healing tires and to tire sealant applicators suited for use therewith.
Self-healing tires typically include a sealant or air barrier composition which is applied to the tire interior by spray application to the interior tire surfaces underlying the tread area, usually with gradual feathering into the sidewalls. Until this invention, however, tires of this type were fabricated using uneconomical application techniques which did not afford automatic or mass production treatment of a large number of tires. Consequently, in many practical cases, sealant application to tires of this type was effected manually, or on an essentially piecemeal basis, or both. More specifically, application of commercial tire sealants customarily was accomplished by first rotating the tire past a stationary sealant applicator at an application station, and then transporting the tire to a curing station at which the tire was rotated for a sufficient time to allow the sealant to set-up while evaporating solvent therefrom, if any.
Early examples of these and other tire application apparatus of this type are disclosed in U.S. Pat. Nos. 1,471,787; 1,474,654 and U.S. Pat. No. Re. 14,765, although all of the aforementioned patents pertain to fabrication of self-lubricating tube-type tires instead of modern tubeless self-healing tires. More recent examples of various tire treatment apparatus and methods especially suited for cleaning tubeless tires in preparation for sealant application, or application of fluid air barrier coatings, are disclosed in U.S. Pat. Nos. 3,825,965 and 3,849,819. With the exception of the aforementioned U.S. Pat. No. 1,474,654, the apparatus and methods disclosed in the aforementioned patents accomplish sealant application on a piecemeal basis. U.S. Pat. No. 1,474,654 offers simultaneous rotation of several tires at various stages of treatment; however, the tires are conveyed from treatment station to treatment station in end-to-end coplanar alignment and, therefore, in most practical applications in which production space is limited, the number of tires which can be treated at one time is effectively limited, depending upon a number of tires which can be accommodated by existing production space end-to-end.